Currently in order to drink liquid food products from a disposable container of liquid food products using a drinking tube or a straw, an opening should be provided on the container or the cap thereof, whereby the drinking tube is inserted into the container for drinking the liquid in the container. The currently available container of liquid food products or the cap thereof has only one opening for inserting the drinking tube, in one of the following forms:
(A) An opening is provided on a disposable container of liquid food product or a cap thereof for inserting the drinking tube, said opening has a straw hole of which the size is bigger than that the diameter of the drinking tube. For example, the cap of the container usually has one cross-shaped cut (the cut means a break line cut off and then closed), the length of each cut is about 2-3 times of the diameter of the drinking tube. The cross-shaped cut forms four corners that are flexible, so that leakage of the drinking material can be prevented to certain extent when the cap is tightly covered on the cup of liquid food products. The consumer needs to insert the drinking tube through the center of the cross-shaped cuts in order to drink the liquid in the container. The drinking tube pushes the four comers of the cross-shaped cuts to form an opening mouth, providing a relatively large space between the drinking tube and the cross-shaped opening. Due to this space, the atmospheric pressure is applied to the drinking surfaces of the liquid food product inside the container. The consumer, when drinking through the drinking tube, produces a negative pressure in consumer's mouth, thereby the liquid in the container is sucked into the consumer's mouth as the result of the atmospheric pressure applied on the liquid in the container. This is the basic principle of drinking liquid from a container of liquid food products.
(B) For pressurized drinking liquid or liquid food product that needs to be kept its original characteristics, the sealed aluminum containers should be used. An opening area, which is a curve-shaped groove where the wall is thinner and has lower strength as compared to other parts of the container, is provided on the top of the aluminum container. A ring is provided within the opening area. When consumer pulls the ring, the opening area is opened by either pulling the opening area up or pressing the opening area down at the opposite side of the ring, until the opened area is big enough for inserting the drinking tube. The shape of the opening area should be designed to allow easy opening, and to prevent hurting consumer's fingers. The opening area is normally not round and is much larger than the diameter of the drinking tube, allowing easy drinking operation (as described in the previous paragraph). Sometimes the ring allows the consumer to take out the entire opening area or the entire cap, for providing easy access to the liquid material by using spoons or by drinking directly without drinking tube.
(C) Another type of container for liquid food products that needs to be kept fresh has a pre-defined round hole for inserting the drinking tube. The diameter of the straw hole is slightly bigger than that of the drinking tube. The straw hole is sealed with a material that can be penetrated by the drinking tube when consuming. The sealed container ensures the freshness of the liquid inside. This type of container is mostly used with “paper packaging/soft packaging” wherein the multi-layer composite paper and aluminum foil material is used to form a container box, which is then sealed after being filled with liquid food product. When consumer drinks the liquid by forcibly inserting the drinking tube into the pre-defined and sealed round straw hole, the container can be deformed by the atmospheric pressure or by hand squeezing, in order to allow the consumer to drink the liquid food products inside easily.
These current methods wherein the drinking tube is inserted into one opening straw hole have following disadvantages and problems:
(1) When halting temporarily drinking the above-mentioned packaged liquid food products, with drinking tube already inserted into the container of liquid food products , the end of the drinking tube outside the container is easily exposed to possible contamination of dust, insects, virus, bacteria or other biological materials, especially in public places. When subsequently utilizing the drinking tube again, the contaminated materials on the end of the drinking tube outside the container will enter the consumer's mouth. The problem can be prevented only if the end of the drinking tube outside the container is continuously kept in consumer's mouth.
(2) The packaged liquid food products according to previously mentioned method (A) or (B) also has the contamination problems where dust, insects, virus and bacteria etc. can enter the container through the drinking tube or the straw hole whose size has to be larger than the diameter of the drinking tube in order to allow air to enter the container, therefore causing health problems, especially when drinking in public places.
(3) The packaged liquid food product according to method (A) or (B) further has problems of accidentally spraying the liquid out by shaking or turning sideways the container when the consumer is walking or traveling in an airplane or on a boat. The reason of spraying out is because of the fact that the size of the straw hole should be larger than the diameter of the drinking tube for allowing entrance of air, as mentioned before. The spraying out may cause contamination to environment or clothes etc.
(4) When drinking the packaged liquid food products according to method (C) by inserting the drinking tube into the sealed round straw hole through the sealing material, the consumer may have difficulties sucking out the liquid since the drinking tube is tightly surrounded by the straw hole. If, on the other hand, the consumer intentionally or accidentally opens up the straw hole to larger size, the problems of above-mentioned contamination or leakage could occur. Furthermore, if the consumer accidentally squeezes the liquid food product container that is made of flexible materials, the liquid can be easily ejected from the drinking tube, thus causing contamination to environment or clothes.